MySociety Elections Challenge

Submission for My Society's developer position coding challenge.

My submission uses node.js, MongoDB and Socket.io to create a live-updating app where you can submit your vote, and a pie-chart updates continually to show the votes as they come in. Votes are stored in the database, along with running totals for each of the parties in each of the constituencies and across the whole country.

I've run this on Windows 7 (64bit) and tested it in the latest Chrome and Firefox browsers. It should be able to run equally well under Linux or Mac, and in other browsers too, but I didn't have time to check.

Limitations

I've intentionally limited the constituencies to 3, and the parties available are fixed and the same for each. This was to make the interface and database simpler and to save time. Because of the time constraints, I've not been able to make much effort to avoid voting fraud, currently the system just checks that you supply a unique-looking email address for each vote, but it doesn't validate that you really own this email address.

Required Software

• Node.js server
• MongoDB database server running at localhost with no username or password

Installation

Assuming you already have the required software setup, all you need to do is clone the repository, and then on the command-line, cd to the project directory and type:

node server.js

To run the server.

Then navigate to: http://localhost:3000 to see the site

Usage

The pie chart shows the percentage of votes each party has received. You can submit a vote using the form below it. Only one vote per email address is allowed. The pie chart will update periodically to show the votes that are coming in.

By default the page shows the total of all votes across all the constituencies. To see votes for a specific constituency, click on one of the links at the top.

Optional Extra Demo

I thought it would be fun to test it out with a simulation of the 2010 General Election. Outside of my 4 hours I wrote actionreplay.js which is a MongoDB shell script that randomly updates the vote counts for the UK until they match the real results for the parties in 2010.

To run this, first start the node server as above, and then in a separate terminal, run the following command (or the linux/mac equivalent):

C:\path_to_mongo\mongo.exe localhost:27017/elections --quiet C:\path_to_repo\MySocietyElectionsChallenge\actionreplay.js

Then start your browser and navigate to: http://localhost:3000 to watch things unfold.

It takes a few minutes to run through, you're looking for a number around 43 million in the Total to know it's done.

Future Work

Obviously, 4 hours isn't particularly long to achieve a finished product, so there are plenty of things I'd like to do. In no particular order, these include:

• Write some unit and functional tests for the code
• Cross-browser test the front-end
• Optimise the css/javascript resources and performance test it with a lot of concurrent users
• Extend the options to include all uk constituencies, perhaps with a postcode lookup to find yours, or a map to select them from, or both
• Look at verifying the email before a vote is included, the user could be sent a one-time link which then moves their vote from pending_votes to the real votes table
• Extend the party list to include all parties that are actually in the elections, and link them to the constituencies so that you only see those who actually have a candidate standing in a given constituency
• Improve the interface design
• Add more visualisation options: different graphs, a leaderboard, a map with each constituency coloured in the colour of the currently leading party
• Add the ability to see the uk-wide and constituency-level data side-by-side, so you can pick one or more constituencies and see them all together